diff --git a/README.md b/README.md
index 4cdf341..dc03e02 100644
--- a/README.md
+++ b/README.md
@@ -18,14 +18,14 @@ You would use custom scalars when you want to describe more meaningful behavior
 ## How to install
 To use this library put the following into your gradle config
 
-    implementation 'com.graphql-java:graphql-java-extended-scalars:18.1'
+    implementation 'com.graphql-java:graphql-java-extended-scalars:19.0'
     
 or the following into your Maven config
 
     <dependency>
       <groupId>com.graphql-java</groupId>
       <artifactId>graphql-java-extended-scalars</artifactId>
-      <version>18.1</version>
+      <version>19.0</version>
     </dependency>
 
 > Note:
@@ -39,6 +39,9 @@ or the following into your Maven config
 > use 17.0 or above for graphql-java 17.x and above
 > 
 > use 18.0 or above for graphql-java 18.x and above
+>
+> use 19.0 or above for graphql-java 19.x and above
+
 
 It's currently available from Maven Central.
 
diff --git a/build.gradle b/build.gradle
index 4544179..f019774 100644
--- a/build.gradle
+++ b/build.gradle
@@ -31,6 +31,12 @@ version = releaseVersion ? releaseVersion : getDevelopmentVersion()
 println "Building version = " + version
 group = 'com.graphql-java'
 
+if (JavaVersion.current() != JavaVersion.VERSION_1_8) {
+    def msg = String.format("This build must be run with java 1.8 - you are running %s - gradle finds the JDK via JAVA_HOME=%s",
+            JavaVersion.current(), System.getenv("JAVA_HOME"))
+    throw new GradleException(msg)
+}
+
 sourceCompatibility = 1.8
 targetCompatibility = 1.8
 
@@ -41,7 +47,7 @@ repositories {
 
 
 dependencies {
-    compile "com.graphql-java:graphql-java:18.1"
+    compile "com.graphql-java:graphql-java:19.2"
 
     testImplementation 'org.spockframework:spock-core:1.3-groovy-2.5'
     testImplementation('org.codehaus.groovy:groovy:2.5.13')